Embodiments relate to a light emitting device, a light emitting device package, and a lighting system.
Light emitting diodes (LED) are semiconductor devices that convert current into light.
A wavelength of light emitted from the respective LEDs is varied according to a semiconductor material used for manufacturing the LED. This is done because a wavelength of the emitted light depends on a band-gap of semiconductor material. The respective band-gaps represent an energy difference between a valence band electrons and conduction band electrons.
As luminance of LEDs is increased recently, the LEDs are being used as light sources for displays, vehicles, and illuminations. Also, LEDs emitting highly efficient white light may be realized by using a fluorescent substance or combining LEDs having various colors.